Shoe-sewing machine



March 26, 1929.

J. SUNDER ET AL SHOE SEWING MACHINE Original Filed Dec. 21, 1925 2 Sheets-Sheet 1 March 26, 1929. J. SUNDER ET AL 1,706,756

S-HOE SEWING MACHINE Original Filed 92 2 Sheets-Sheet 2 Patented Mar. 26, 1929.

UNITED STATES PATENT OFFICE.

FIRM OF ADRIAN- & BUS CH, 0F OBERURSEL, GERMANY.

sHoE-snwmo MACHINE.

Original application filed December 21, 1923, Serial No. 682,088, and in Germany December 28, 1922.

Divided and this application filed February 11, 1925. Serial No. 8,5

This invention relates to improvements in sewing machine take-ups, and more'particularly to that class of take-ups in which a take-up lever is fulcruined on a fixed shaft and is connected at one end by means of links to a rotary actuating crank. The invention has for its object to impart tothe free end of the take-up such an oscillatory movement as to move slowly upwards and to deliver uniformly the thread while the loop is formed and to move thereafter rapidly down to take care of the surplus of the thread. This object of the invention is attained by means of the novel features of construction and combi* nation of parts, as hereinafter set forth in detail, the present application being a division of application No. 682,088, filed December 21, 1923.

In the drawings Figs. 14 illustrate the different positions of the take-up and the cooperating parts of a sole sewing machine embodying the present invention, Figs. 1-8 show the moving mechanism of the take-up in different positions. Fig. 9 is a diagram of the takc-up mechanism.

Figs. 1 to 4 illustrate the succeeding working positions of the take-up 34 and the cooperating sewing instruments of a sole sewing machine. In the position shown in Fig. 1 the needle has pierced the work and catches the thread; the take-up lever '34 has reached theend of its downward stroke. The thread linger 31 pulls the thread rearward and the looper manipulates the thread into the barb of the needle 18. The needle begins to return and to draw the loop through the work. In the wholly retracted position of the needle the loop spreader 20 opens the loop (see Fig. 2) to be taken by theorotating hook 21. To ensure the operation of the revolving hook, the needle 18 advances a little and frees the loop from the barb, see Fig. 3. Finally the needle returns to its most retracted position, see Fig. 4. By the rotation of the hook 21 the loop is passed .round the bobbin case 36 until it reaches the highest point of the case whereupon the loop slips down from the case. While the thread is caught by the needle and the loop is formed and passed around the bobbin case the take-up lever must slowly and uniformly deliver the thread. On the contrary the loop gliding down from the bobbin case must be taken care of by a rapid movement of the take-up lever. These movements of the take-up lever are obtained by the following arrangement.

The take-up 34 is formed by a two-armed lever revolubly mounted on the fixed shaft XXIX of the machine frame and connected at XXVIII to the toggle lever 37. On the rotating shaft 2 of themachine is fastened I ing lever 44 by the pivot XXVI, the swinging lever 44 itself being rotatably mounted on the shaft XXVII.

The eccentric turns in the direction indicated by the arrow and assumes succeedingly the positions shown in Figs. 5 to 8. From an .inspection of the drawings it will be apparent that the upward movement of the take-up lever from the position shown in Fig. 5 to the position in Fig. 8 corresponds to an angle of rotation much greater than the angle corresponding to the downward movement of the take-up lever. The upward movement and the downward movement of the take-up lever are of the same extent, but they are performed with different velocities. The upwardmovement corresponds to nearly of the revolution of the eccentric and the downward movement corresponds tothe remaining of the revolution. The upward movement is therefore a comparatively slow one and serves for the delivery of the thread while the comparatively rapid downward movement serves for the stitch set-ting. The parts 38, 40, 41 driving four side linkage, the machine frame between the shafts 2 and XXIV representing the fourth immovable side of the linkage. diagram of Fig. 9. The eccentric 38 of form three sides of a F igs. 58 is e uivalent to the crank 38 of Fl x h 9, connected by the rod 40 to the pivot XXIII of the swinging lever 41. The four pivots of the linkage are XXI, XXII, XXIII and I XXIV and the linkage itself'may be denominated as four side rotating linkage. The connecting rod 40 has the prolongation 42 beyond the pivot XXII (equivalent to the strap 39) to the pivot XXV. On the other hand the parts 44, 37 and the upper arm of the lever 84: form :1 secontl tour sicle linkage with the pivots XXVII, XXVI, XXVIH, and XXIX. But this linkage comprises no revolving parts and may therefore be denomitatecl' an oscillating linkage. Both linkages are connected to each other by the link 43. r

During the rotation of the eccentric or the crank 38 the pivot XXII describes the are my and the pivots XXV, XLVI describe the corresponding paths aag/ anal mg respec tively Which are nearly reccen g'mzir to eucl'i other. In View of the fact that the path 2 2 represents the Whole oscillation of the pivot XX 1 it will be apparent that the s "inging lever Will mve' ra iiclly upwards along; the path rdy While the cranlep'ivot XXII describes the are soy and theti-t will move crzmk 38 describes the rest of the circle.

ltiovements of small extent on the line wy cause movements of great extent on the line 3 What We claim is:

In a shoe sewing machine, a rotating eccentric, a swinging lever, a strap coacting with the eccentric and connectecl to the swinging l ver, a winging take-up lever, and a connection between the strap of the rotating eccentric and to the tztleiiplever respectively and hinged to each other at their inner encls for the purpose specified.

In testimony Whereot We afiix our signatures. JAKOB SUNDER;

EBERHARDT RENNO'. 

